Wiseco PK1238 Piston Kit - 79mm 04-05 KX250F 04-06 RMZ250 4842M

The Wiseco PK1238 is a complete top-end piston kit designed for the 2004–2005 Kawasaki KX250F and 2004–2006 Suzuki RMZ250. This kit delivers everything needed for a professional-quality overbore or top-end rebuild, with a 79mm bore diameter (overbore size 4842M).

Wiseco forged pistons are manufactured using high-strength 2618 aluminum alloy and precision CNC machined to tight tolerances, offering superior strength, reduced weight, and improved thermal management compared to cast OEM-style pistons. Each piston features Wiseco's ArmorGlide skirt coating to reduce friction and extend component life.

Kit Contents:

• Forged piston(s) — 79mm bore, engineered for high-performance 4-stroke motocross applications
• Piston ring set — properly sized for the 79mm overbore
• Wrist pin (piston pin) — high-strength chrome-moly steel
• Circlips (retainer clips) — for secure wrist pin retention
• Overbore head gasket — matched to the 79mm bore for proper sealing

This kit is ideal for racers and enthusiasts looking to restore or upgrade the top end of their 250F motocross machine. The included overbore head gasket ensures a proper compression seal at the new bore size, making this a true all-in-one solution for engine rebuilds.